Lifting and stacking device



Oct. 25, 1966 s n-H LIFTING AND STACKING DEVICE Filed June 25, 1965 INVENTOR United States Patent 3,280,939 7 7 LIFTIN G AND STACKING DEVICE Alfred E. Smith, 1525 Dundas St. W., Toronto,

Ontario, Canada I Filed June 25, 1965, Ser. No. 466,921 7 Claims. (Cl. 182-16) This invention relates to a mobile lifting device, and more particularly to a simplified inexpensive lightweight folding type of lifting device that may be used especially in confined areas where lift fork trucks are too bulky to maneuver successfully.

Many warehouses utilize forms of racks having upper and lower levels, and in some cases more than two levels, upon which merchandise and like products are stored. Aisles between the rows of racks may be of sufficient width to enable fork lift trucks to pass through. However, in order to place merchandise in the upper levels of the racks, additional space is required for the fork lift to turn. When the merchandise is of a size and weight that is beyond the lifting capability of the average man a fork lift truck has to be employed, and the aisles have to be made of a width sufiicient to accommodate the fork lift in carrying out its function, particularly permitting the fork lift to turn towards the rack.

However, to make the aisles wide enough to accomplish this, in many instances, may lead to a wasteful use of floor area. Moreover, unless the size of the merchandise, or like product, is of a size that merits use of the fork lift, investment in a fork lift becomes an unnecessary waste of funds.

Many instances nevertheless can be brought to mind wherein a lifting device may save both time and labour, and at the same time add to the safety of the warehouse staff. For instance, a ladder, or steps, may appear as an answer to the problem of lifting merchandise to the upper levels of the racks, or of bringing it from the higher levels to the ground. It will become evident upon consideration of this, however, that for a warehouse man to carry merchandise in his arms in either direction constitutes an unnecessary hazard since he must with at least one hand release the ladder while making his ascent or descent. Alternatively, the merchandise may be lifted by a second warehouse man to the first one already on the ladder who receives the items and places them in the rack. This second way, while possibly being safer, increases the labour cost.

The object of this invention, therefore, is to provide an inexpensive lifting device that may be operated by one man for lifting items from the floor level to the upper levels of warehouse racks.

A further object of this invention is to provide a lifting device that may be used in confined areas where a forklift truck or like power operated vehicle cannot successfully be operated. A further object of this invention is to provide a lifting device which may be folded away when not in use.

A still further object of this invention is to provide a mobile lifting device which may be moved over the floor while the lifting platform is in an elevated position, as is possible with a fork lift truck, thereby to reduce operation of the lifting device as it is moved to each rack.

A yet further object of this invention is to provide a mobile lifting device which may be used in the construction industry, and the like, during building operations wherever materials have to be raised within reach of a worker above ground level, as for instance a brick layer, a painter or a plasterer working upon the upper portions of walls, ceilings, and so on.

Further objects and advantages will become apparent 3,280,939 Patented Oct. 25, 1966 from the following description taken in connection with the accompanying drawings, in which:

FIG. 1 is a perspective view of a preferred embodiment of this invention in a typical operating position.

FIG. 2 is a side view of the embodiment depicted in FIG. 1 illustrating the manner in which support arms foldas the device is folded from its operating position.

FIG. 3 is a side view of the embodiment depicted in FIG. 1 completely folded in a space saving storage position.

Referring to FIG. 1 in greater detail, reference numeral 10 designates generally a mobile lifting device having a generally rectangular frame constructed from two vertical I beam supports 11 connected at their upper and lower ends between inner flanges 12 the upper cross strut 13 and lower cross strut 14. At the upper end of each I beam support is, pivotably secured to outer flanges 15,

a forward leg 16 and a rear leg 17, the lower end of each forward leg having a wheel 18. Each forward leg 16 is connected to the lower portion of the appropriate I beam support 11 with a brace 19 hinged approximately in the middle thereof, each brace 19 being pivotable upon both the forward leg 16 and the I beam support 11. Braces 19 are restricted to a folding movement in an upward direction only, at hinges 20, as illustrated best in FIG. 2; however, a sleeve 21 is provided that may be slid over each hinge 20 when lifting device 10 is in the operating position depicted in FIG. 1, to prevent accidental folding of the braces 19. Similar rear braces 19 are provided to connect each rear leg 17 with the appropriate I beam support 11, each rear brace 19 being pivotable both at the rear leg 17 and the I beam support 11 and also having a sleeve 21 to prevent folding of the device accidentally during use.

A platform support frame designated generally by reference numeral 23 is slidably engaged with vertical supports 11 to move in an upward and downward direction therebetween. Platform support frame 23 comprises a pair of upright attachment channels 24 of U cross section, oppositely and outwardly encompassing respective inner flanges 12 and centre channel member 25 as shown in FIG. 1. Pivotably secured to the upper ends of support channels 24 are pairs of rollers 26 engaging the opposite faces of centre channel member 25 between the inner and outer flanges 12 and 15. Similar pairs of rollers 26 are provided at the lower ends. Channels 24 are connected by upper and lower cross bars 27 and 28.

A winch 29 is provided, secured to the upper cross strut 13 and hooked to upper cross bar 27 to lift platform support frame 23. Winch 29 should preferably be of the non-slip type operated by an endless chain 30 so that platform support frame 23 is maintained in any descend position upon an operator releasing endless chain 30 to continue either loading or unloading the lifting device 10 in the manner hereinbelow described.

With further reference to FIG. 1.

A loading platform 31 is hingeably secured to the forward edge 32 of upper cross bar 27, the movement of hinges 33 permitting the movement of platform 31 in a downward direction from the operating position depicted in FIG. 1 to the folded position depicted in FIG. 3.

A- standing platform 34 is similarly provided below loading platform 31, hingeably secured to lower cross beam 28 and extending therefrom rearwardly as illustrated in the drawings. Hinges 35 securing standing platform 34 permit upward movement thereof from a level operating position, as illustrated, to the folded position illustrated in FIG. 3. Platform braces 36 are pivotably secured to the outer edges 37 and 38 to maintain platforms 31 and 34 in parallel horizontal openating positions as shown in FIG. 1. Braces 36 are joined at their opposite ends condition.

to vertical support 11. It should be noted that these platform braces 36 are similar to' those braces 19 and 22 connecting the forward and rear legs 16 and 17 to the vertical supports 11, since each platform brace 36 is adapted to fold about a centrally located hinge 39; forward braces 36 are joined to loading platform 31, folding upwardly to permit loading platform 31 to be lowered, and rear braces 36 folding downwardly to permit standing platform 34 to be lifted upwardly to a storage position, as best shown in FIG. 2. Sleeves 40 are provided upon braces 36 to circumpose hinges 39 while this invention is in use to support firmly both platforms 31 and 34 in their horizontal operating positions, and prevent accidental folding of the invention through jolting thereof during use.

It is evident that vertical supports 11 may be constructed in various heights, provided the dimension of the legs correspond in proportion thereto. Also, the height of loading platform 31 above standing platform 34 may be varied. However, the distance between loading platform 31 and standing platform 34 should be approximately three feet since this has been found to be a height that is practical for the average man who will operate this invention. A useful height for the invention has been found to be generally about ten feet, since higher frames require wider floor areas to receive legs at a required safe span and available floor area to receive legs at a required safe span and available floor area is primarily therefore the limiting factor as to the height of the device. However, various designs may be utilized according to particular needs for the invention. For example in the construction industry a sturdier design would be required for lifting the generally heavier loads that are encountered than is necessary in a toy warehouse wherein the merchandise is commonly bulky but comparatively light in weight.

The lifting device may be moved from one location to another in operating position in loaded or unloaded To move the device an operator simply lifts the rear legs 17 and either pushes the device ahead, or pulls it back upon the forwardly mounted wheels 18 previously noted, to the next desired location. In order to assist an operator move the lifting device folding handles 42 may be provided pivotably mounted on rear legs 17, and adapted to fold downwardly from the horizontal position to a completely folded position, as clearly illustrated in FIGS. 2 and 3.

To load the device the loading platforms 31 is lowered and merchandise 43 placed thereon. The operator 41, depicted by phantom lines in FIG. 2, thereupon raises both the loading platform 31 and the lifting platform 34 to the required height by stepping upon standing platform 34 and actuating winch 29 which raises the platform support frame 23 to the required height for stacking. He thereupon unloads platform 31, and then lowers the platform support frame 23 for a second load by actuating winch 29 in a counterwise direction. To unload merchandise, and the like, from warehouse racks the operator follows the reverse of the procedure given above.

:While a particular embodiment has been described and illustrated, it will be understood that this is intended as illustrative of the principle of the invention rather than limiting to the particular construction given, and accordingly modifications and equivalents may be made without departing from the inventive concept as defined in the appended claims.

I claim:

1. A lifting and stacking device comprising a generally rectangular outer frame having upright parallel side support beams and relatively shorter upper and lower cross beams secured to upper and lower ends of said support beams respectively, arectangular platform support frame having upright side bars and upper and lower cross struts joining the upper and lower ends of said side bars respectively, connecting means on said side bars engaging said side support beams to permit vertical movement ing provided with second adjustable support means to maintain said standing platform in a horizontal plane so that an operator may stand thereon during the loading and unloading of said loading platform, said second support means permitting said standing platform to be raised from said horizontal plane to a vertical plane against the rear of said platform support frame, control means for raising and lowering said platform support frame With respect to said outer frame, and leg attachment means secured to said outer frame to support said outer frame in a vertical position during use of lifting and stacking device.

2. A lifting and stacking device comprising a generally rectangular outer frame having upright parallel side support beams and relatively shorter upper and lower cross beams secured to upper and lower ends of said support beams respectively, a rectangular platform support frame having upright side bars and upper and lower cross struts joining the upper and lower ends of said side bars respectively, connecting means on said side bars engaging said side support beams to permit vertical movement of with first adjustable support means to maintain said loading platform in a horizontal plane for the purpose of loading and unloading said loading platform, said support means permitting said loading platform to be lowered from said horizontal plane to a vertical plane against the front of said platform support frame, a rearwardly extending standing platform hingeably mounted upon said lower cross strut, said standing platform being provided with second adjustable support means to maintain said standing platform in a horizontal plane so that an operator may stand thereon during the loading and unloading of said loading platform said second support means permitting said standing platform to be raised from said horizontal plane to a vertical plane against the rear of said platform support frame, control means for raising and lowering said platform support frame with respect to said outer frame, and leg attachment means secured to said outer frame to support said outer frame in a vertical position during use of lifting and stacking device, each said side beam of said outer frame has an I configuration comprising inner and outer flanges and a centrally disposed web, each said side bar of said platform support frame defining a channel, said channel overlapping said inner flanges and said web of adjacent said side beam, said connecting means in each said side bar comprising at least one pair of rollers rotatably mounted within said channel of said side bars in contact with said web, said inner and outer flanges disposed each side of said web overlapping said pair of rollers to prevent lateral displacement of said rollers from said web.

3. A lifting and stacking device as defined in claim 2 in which said first support means comprises at least one first bar provided with a substantially central hinge, said bar being pivotable at one end on one said side bar of said platform support frame below said upper cross strut thereof and pivotably mounted at its other end upon an edge of said loading platform remote from said upper cross strut, said second support means comprises at least one second bar provided with a substantially central hinge, said second bar being pivotable at one end on one said side bar of said platform support frame above said lower cross strut thereof and pivo tably mounted at its other end upon an edge of said standing platform remote from said lower cross strut.

4. A lifting and stacking device as defined in claim 2 in which said first support means comprises at least one first bar provided with a substantially central hinge, said bar being pivotable at one end on one said side vbar of said platform support frame below said upper cross strut thereof and pivotably mounted at its other end upon an edge of said loading platform remote from said upper cross strut, said second support means is a foldable brace attached at one end to an edge of said standing platform remote from said platform support frame and I at its other end to said platform support frame above said lower cross strut.

5. A lifting and stacking device as defined in claim 2 in which said control means is a conventional pulley winch of the non-slip type attached to said upper cross beam of said outer frame and secured to said upper cros strut of said platform support frame.

6. A lifting and stacking device as defined in claim 2 in which said leg attachment means comprises a forward leg and a rear leg pivotably secured at their upper ends to each said side support beam substantially at the upper end thereof, said legs being provided with restricting means secured to said outer frame thereby to prevent said legs moving away from said frame more than a given distance in an open position, said restricting means being provided with locking means in said open position thereby to prevent said legs moving toward said outer frame in a folded position, each said forward legs being provided with a rotatable wheel thereby to permit movement of said device upon lifting said rear legs from the ground.

7. A lifting and stacking device as defined in claim 2 in which each said rear leg being supplied with a pivotable handle, said handle being movable between a folded position against said leg to an operating position substan tially perpendicular to said leg thereby to assist an operator in lifting said rear legs from the ground and controlling movement of said device along the ground in said open position of said forward and rear legs.

References Cited by the Examiner UNITED STATES PATENTS REINALDO P. MACHADO, Primary Examiner. 

1. A LIFTING AND STACKING DEVICE COMPRISING A GENERALLY RECTANGULAR OUTER FRAME HAVING UPRIGHT PARALLEL SIDE SUPPORT BEAMS AND RELATIVELY SHORTER UPPER AND LOWER CROSS BEAMS SECURED TO UPPER AND LOWER ENDS OF SAID SUPPORT BEAMS RESPECTIVELY, A RECTANGULAR PLATFORM SUPPORT FRAME HAVING UPRIGHT SIDE BARS AND UPPER AND LOWER CROSS STRUTS JOINING THE UPPER AND LOWER ENDS OF SAID SIDE BARS RESPECTIVELY, CONNECTING MEANS ON SAID SIDE BARS ENGAGING SAID SIDE SUPPORT BEAMS TO PERMIT VERTICAL MOVEMENT OF SAID PLATFORM SUPPORT FRAME WITHIN SAID RECTANGULAR OUTER FRAME, A FORWARD LOADING PLATFORM HINGEABLY MOUNTED TO SAID UPPER CROSS STRUT, SAID PLATFORM BEING PROVIDED WITH FIRST ADJUSTABLE SUPPORT MEANS TO MAINTAIN SAID LOADING PLATFORM IN A HORIZONTAL PLANE FOR THE PURPOSE OF LOADING AND UNLOADING SAID LOADING PLATFORM, SAID SUPPORT MEANS PERMITTING SAID LOADING PLATFORM TO BE LOWERED FROM SAID HORIZONTAL PLANE TO A VERTICAL PLANE AGAINST THE FRONT OF SAID PLATFORM SUPPORT FRAME A REARWARDLY EXTENDING STANDING PLATFORM HINGEABLY MOUNTED UPON SAID LOWER CROSS STRUT, SAID STANDING PLATFORM BEING PROVIDED WITH SECOND ADJUSTABLE SUPPORT MEANS TO MAINTAIN SAID STANDING PLATFORM IN A HORIZONTAL PLANE SO THAT AN OPERATOR MAY STAND THEREON DURING THE LOADING AND UNLOADING OF SAID LOADING PLATFORM, SAID SECOND SUPPORT MEANS PERMITTING SAID STANDING PLATFORM TO BE RAISED FROM SAID HORIZONTAL PLANE TO A VERTICAL PLANE AGAINST THE REAR OF SAID PLATFORM SUPPORT FRAME, CONTROL MEANS FOR RAISING AND LOWERING SAID PLATFORM SUPPORT FRAME WITH RESPECT TO SAID OUTER FRAME, AND LEG ATTACHMENT MEANS SECURED TO SAID OUTER FRAME TO SUPPORT SAID OUTER FRAME IN A VERTICAL POSITION DURING USE OF LIFTING AND STACKING DEVICE. 